Screen installation has become one of the necessary devices in window structures. Recently, many windows using foldable screen have been adopted in order to isolate mosquitos from the interior, and avoid blocking the view from the exterior; the mosquitos can be isolated from the interior when the screen stretches, and a view without obstacles can be provided when the screen folds.
Currently, the foldable screen provides an end disposed on a activity frame and another end disposed on a fixed frame, and drawing wires pass through a surface of the screen; The screen stretches or folds without inclining and falling through the tension of the wires, and a structure of the screen window provides with a wire drawing tightness controller for controlling the tension of the wires, such as the references from Taiwan Patent No. I260364, and No. I228567. However, the wire drawing tightness controllers from the references are disposed within the activity frame or the fixed frame, and the drawing wires are also disposed within the said frames or other frames of the foldable screen, thus drawing wires can be knotted on the wire drawing tightness controller to achieve the function of the expected controller. However, when the window of the foldable screen is removed and replaced, the frame provided with the drawing wires and the wire drawing tightness controller needs to be disassembled first, and the drawing wires and the wire drawing tightness controller are removed from the frame to replace the screen, thus replacing screen results in inconvenience.
In order to improve the above disadvantage, Taiwan Patent No. M383624 discloses a drawing wire flexible mount of foldable screen window 1, which comprises a wire bolt 11 and a shell cover 12 (see FIGS. 1 and 2), wherein an end of the wire bolt is provided with a ditch, and drawing wires L are fixed in the ditch (not shown). Another end of the wire bolt is provided with a polygonal plug 111 formed with a screw hole 112. The shell cover 12 is configured to receive the wire bolt 11, and two sides of the shell cover 12 corresponding to a window frame A are formed with an embedded slot 121 to embed in the window frame A. Therefore, an workpiece is inserted into the screw hole 112 of the polygonal plug 111 to turn the wire bolt 11 when using it, and the drawing wires L winds around the wire bolt 11 or not to achieve the function of controlling the drawing wires L tightness.
As described above, the structure of Patent No. M383624 can be embedded from the external part of the window frame to improve the inconvenience that the wire drawing tightness controller is disposed within the window frame. However, when the window frame uses extrusion molding, the mold is used for a long time, causing abrasions, and the size of the window frame is sometimes over the range of the original settings. Thus the installation of the shell cover is difficult, and the structure of Patent No. M383624 cannot exert the function of controlling the drawing wires tightness.